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Journal of Morphology Dec 2021The present review summarizes available information on the contribution of regenerating nerves to the process of regeneration in the tail of lizards. From the last three... (Review)
Review
The present review summarizes available information on the contribution of regenerating nerves to the process of regeneration in the tail of lizards. From the last three segments of the spinal cord and ganglia proximal to the regenerating tail, motor, sensory somatic and autonomous nerves regenerate and richly innervate the growing blastema. However, experimental studies have indicated that peripheral nerves are not essential for stimulating the regeneration of the tail that instead is mainly sustained by the interaction of the apical ependyma with the wound epidermis. Ganglion neurons innervating the regenerating blastema increase their size and some satellite cells multiply but no ganglion neurons are regenerated. Numerous Schwann cells proliferate to keep pace with nerve regeneration, and they form myelin starting from 3 to 4 weeks of tail regeneration. The hypertrophic ganglion neurons synthesize growth factors and signaling proteins such as FGFs and Wnts that are transported into the regenerating blastema through the regenerating nerves. Nerves form synaptic-like contacts with mesenchymal cells or fibroblasts at the tip of the regenerating blastema but not synaptic boutons. These terminals may discharge stimulating factors that favor cell proliferation but this is not experimentally demonstrated. Most of the innervation is directed to differentiating muscles where nerve endings form cholinergic motor-plates. Transcriptome data on the regenerating blastema-cone detect up-regulation of various genes coding for ionic channels, neurotransmitter receptors and signaling proteins. The latter suggests that the neurotrophic stimulation may control cell proliferation but is most directed to the functionality of regenerating muscles.
Topics: Animals; Epidermis; Ganglia, Spinal; Lizards; Muscles; Spinal Cord
PubMed: 34609016
DOI: 10.1002/jmor.21416 -
Regional Anesthesia and Pain Medicine Jun 2023The use of neuromodulation systems is increasing for the treatment of various pathologies ranging from movement disorders to urinary incontinence to chronic pain... (Review)
Review
The use of neuromodulation systems is increasing for the treatment of various pathologies ranging from movement disorders to urinary incontinence to chronic pain syndromes. While the type of neuromodulation devices varies, they are largely categorized as intracranial (eg, deep brain stimulation), neuraxial (eg, spinal cord stimulation, dorsal root ganglion stimulation, and intrathecal drug delivery systems), or peripheral (eg, sacral nerve stimulation and peripheral nerve stimulation) systems. Given the increasing prevalence of these systems in the overall population, it is important for anesthesiologists, surgeons, and the perioperative healthcare team to familiarize themselves with these systems and their unique perioperative considerations. In this review, we explore and highlight the various neuromodulation systems, their general perioperative considerations, and notable special circumstances for perioperative management.
Topics: Humans; Transcutaneous Electric Nerve Stimulation; Spinal Cord Stimulation; Chronic Pain; Spinal Nerves; Anesthetics
PubMed: 37080581
DOI: 10.1136/rapm-2022-103660 -
Ultraschall in Der Medizin (Stuttgart,... Oct 2023The sciatic nerve (SN) is the biggest nerve in the human body and innervates a large skin surface of the lower limb and several muscles of the thigh, leg, and foot. It...
The sciatic nerve (SN) is the biggest nerve in the human body and innervates a large skin surface of the lower limb and several muscles of the thigh, leg, and foot. It originates from the ventral rami of spinal nerves L4 through S3 and contains fibers from both the posterior and anterior divisions of the lumbosacral plexus. After leaving the neural foramina, the nerve roots merge with each other forming a single peripheral nerve that travels within the pelvis and thigh. Non-discogenic pathologies of the SN are largely underdiagnosed entities due to nonspecific clinical tests and poorly described imaging findings. Likewise, to the best of our knowledge, a step-by-step ultrasound protocol to assess the SN is lacking in the pertinent literature. In this sense, the aim of the present manuscript is to describe the normal sono-anatomy of the SN from the greater sciatic foramen to the proximal thigh proposing a standardized and simple sonographic protocol. Then, based on the clinical experience of the authors, a few tips and tricks have been reported to avoid misinterpretation of confounding sonographic findings. Last but not least, we report some common pathological conditions encountered in daily practice with the main purpose of making physicians more confident regarding the sonographic "navigation" of a complex anatomical site and optimizing the diagnosis and management of non-discogenic neuropathies of the SN.
Topics: Humans; Sciatic Nerve; Peripheral Nervous System Diseases; Ultrasonography
PubMed: 37832532
DOI: 10.1055/a-2095-2842 -
Scientific Reports Apr 2020The avian transition from long to short, distally fused tails during the Mesozoic ushered in the Pygostylian group, which includes modern birds. The avian tail embodies...
The avian transition from long to short, distally fused tails during the Mesozoic ushered in the Pygostylian group, which includes modern birds. The avian tail embodies a bipartite anatomy, with the proximal separate caudal vertebrae region, and the distal pygostyle, formed by vertebral fusion. This study investigates developmental features of the two tail domains in different bird groups, and analyzes them in reference to evolutionary origins. We first defined the early developmental boundary between the two tail halves in the chicken, then followed major developmental structures from early embryo to post-hatching stages. Differences between regions were observed in sclerotome anterior/posterior polarity and peripheral nervous system development, and these were consistent in other neognathous birds. However, in the paleognathous emu, the neognathous pattern was not observed, such that spinal nerve development extends through the pygostyle region. Disparities between the neognaths and paleognaths studied were also reflected in the morphology of their pygostyles. The ancestral long-tailed spinal nerve configuration was hypothesized from brown anole and alligator, which unexpectedly more resembles the neognathous birds. This study shows that tail anatomy is not universal in avians, and suggests several possible scenarios regarding bird evolution, including an independent paleognathous long-tailed ancestor.
Topics: Alligators and Crocodiles; Animals; Chick Embryo; Chickens; Embryonic Development; Fossils; Genetic Speciation; Lizards; Phylogeny; Spinal Nerves; Tail
PubMed: 32286419
DOI: 10.1038/s41598-020-63264-5 -
Nutrients Oct 2023This study examined the effects of turmeric bioactive compounds, curcumin C3 complex® (CUR) and bisdemethoxycurcumin (BDMC), on mechanical hypersensitivity and the gene...
Turmeric Bioactive Compounds Alleviate Spinal Nerve Ligation-Induced Neuropathic Pain by Suppressing Glial Activation and Improving Mitochondrial Function in Spinal Cord and Amygdala.
This study examined the effects of turmeric bioactive compounds, curcumin C3 complex® (CUR) and bisdemethoxycurcumin (BDMC), on mechanical hypersensitivity and the gene expression of markers for glial activation, mitochondrial function, and oxidative stress in the spinal cord and amygdala of rats with neuropathic pain (NP). Twenty-four animals were randomly assigned to four groups: sham, spinal nerve ligation (SNL, an NP model), SNL+100 mg CUR/kg BW p.o., and SNL+50 mg BDMC/kg BW p.o. for 4 weeks. Mechanical hypersensitivity was assessed by the von Frey test (VFT) weekly. The lumbosacral section of the spinal cord and the right amygdala (central nucleus) were collected to determine the mRNA expression of genes (IBA-1, CD11b, GFAP, MFN1, DRP1, FIS1, PGC1α, PINK, Complex I, TLR4, and SOD1) utilizing qRT-PCR. Increased mechanical hypersensitivity and increased gene expression of markers for microglial activation (IBA-1 in the amygdala and CD11b in the spinal cord), astrocyte activation (GFAP in the spinal cord), mitochondrial dysfunction (PGC1α in the amygdala), and oxidative stress (TLR4 in the spinal cord and amygdala) were found in untreated SNL rats. Oral administration of CUR and BDMC significantly decreased mechanical hypersensitivity. CUR decreased CD11b and GFAP gene expression in the spinal cord. BDMC decreased IBA-1 in the spinal cord and amygdala as well as CD11b and GFAP in the spinal cord. Both CUR and BDMC reduced PGC1α gene expression in the amygdala, PINK1 gene expression in the spinal cord, and TLR4 in the spinal cord and amygdala, while they increased Complex I and SOD1 gene expression in the spinal cord. CUR and BDMC administration decreased mechanical hypersensitivity in NP by mitigating glial activation, oxidative stress, and mitochondrial dysfunction.
Topics: Rats; Animals; Curcuma; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Rats, Sprague-Dawley; Superoxide Dismutase-1; Toll-Like Receptor 4; Spinal Cord; Spinal Nerves; Amygdala; Neuralgia
PubMed: 37892476
DOI: 10.3390/nu15204403 -
Anatomic description of the basivertebral nerve and meningeal branch of the spinal nerve in the dog.Annals of Anatomy = Anatomischer... Jan 2023The existence of the basivertebral nerve and meningeal branch of the spinal nerve has not been proven in dogs to date. The objectives of this study are to 1) determine...
PURPOSE
The existence of the basivertebral nerve and meningeal branch of the spinal nerve has not been proven in dogs to date. The objectives of this study are to 1) determine whether dogs have a meningeal branch of the spinal nerve (MBSN) and a basivertebral nerve (BVN) and to (2) describe anatomical characteristics of these two nerves. Authors also put forward a discussion on the possible clinical relevance of these findings.
MATERIAL AND METHODS
Dissections were performed on six embalmed dogs at the Veterinary Faculty of Barcelona with the use of stereomicroscopy and microsurgery equipment.
RESULTS
The MBSN (grossly) and BVN (grossly and histologically) were identified in the cervical, thoracic, and lumbar region in all dog specimens. In addition, other small fibers (suspected nerves) entering the vertebral body through small foramina close to the end plates were identified. Histological examination of the tissues confirmed the presence of nerve fibers (myelinated and unmyelinated) in suspected BVN samples. Results of the present study indicated that dogs have BVNs. Also, suspected nerve fibers were identified among the epidural fat, running from the intervertebral foramina, that likely represent the MBSN.
CONCLUSION
These findings open up the discussion on extrapolation of treatment options employed in human medicine for "low back pain", such as BVN ablation, which is discussed in this article. Further anatomic and clinical studies of the innervation for the vertebral body, periosteum, vasculature, dorsal longitudinal ligament and anulus fibrosus are necessary to elucidate possible anatomical variants and breed differences as well as potential clinical (e.g., therapeutic) relevance.
Topics: Dogs; Humans; Animals; Spinal Nerves; Low Back Pain; Spine; Dissection; Lumbosacral Region
PubMed: 36183940
DOI: 10.1016/j.aanat.2022.152000 -
Journal of Clinical Neurophysiology :... Jul 2021Comprehensive evaluation of the upstream sensory processing in diabetic symmetrical polyneuropathy (DSPN) is sparse. The authors investigated the spinal nociceptive... (Comparative Study)
Comparative Study
PURPOSE
Comprehensive evaluation of the upstream sensory processing in diabetic symmetrical polyneuropathy (DSPN) is sparse. The authors investigated the spinal nociceptive withdrawal reflex and the related elicited somatosensory evoked cortical potentials. They hypothesized that DSPN induces alterations in spinal and supraspinal sensory-motor processing compared with age- and gender-matched healthy controls.
METHODS
In this study, 48 patients with type 1 diabetes and DSPN were compared with 21 healthy controls. Perception and reflex thresholds were determined and subjects received electrical stimulations on the plantar site of the foot at three stimulation intensities to evoke a nociceptive withdrawal reflex. Electromyogram and EEG were recorded for analysis.
RESULTS
Patients with DSPN had higher perception (P < 0.001) and reflex (P = 0.012) thresholds. Fewer patients completed the recording session compared with healthy controls (34/48 vs. 21/21; P = 0.004). Diabetic symmetrical polyneuropathy reduced the odds ratio of a successful elicited nociceptive withdrawal reflex (odds ratio = 0.045; P = 0.014). Diabetic symmetrical polyneuropathy changed the evoked potentials (F = 2.86; P = 0.025), and post hoc test revealed reduction of amplitude (-3.72 mV; P = 0.021) and prolonged latencies (15.1 ms; P = 0.013) of the N1 peak.
CONCLUSIONS
The study revealed that patients with type 1 diabetes and DSPN have significantly changed spinal and supraspinal processing of the somatosensory input. This implies that DSPN induces widespread differences in the central nervous system processing of afferent A-δ and A-β fiber input. These differences in processing may potentially lead to identification of subgroups with different stages of small fiber neuropathy and ultimately differentiated treatments.
Topics: Adult; Aged; Diabetes Mellitus; Diabetic Neuropathies; Electric Stimulation; Electromyography; Evoked Potentials, Somatosensory; Female; Humans; Male; Middle Aged; Nociception; Reflex; Spinal Nerves
PubMed: 32501945
DOI: 10.1097/WNP.0000000000000691 -
Orthopaedics & Traumatology, Surgery &... Apr 2023Previous studies reported that spinal nerve edema on magnetic resonance myelography (MRM) and leg pain at rest were specifically observed in symptomatic lumbar foraminal...
BACKGROUND
Previous studies reported that spinal nerve edema on magnetic resonance myelography (MRM) and leg pain at rest were specifically observed in symptomatic lumbar foraminal stenosis patients. However, the correlation between leg pain at rest and spinal nerve edema in symptomatic foraminal stenosis has not been reported.
HYPOTHESIS
The purpose of this prospective study is to reveal a correlation between leg pain at rest and spinal nerve edema focusing on the pathophysiology of symptomatic foraminal stenosis.
PATIENTS AND METHODS
Clinical findings and MRM findings were surveyed among 30 patients with symptomatic foraminal stenosis diagnosed by MR imaging (MRI) and selective nerve root block. Comparisons of patient characteristics and clinical findings between the prevalence and absence groups of spinal nerve edema on MRM were analyzed. A correlation between the visual analogue scale (VAS) for leg pain at rest and the spinal edema ratio calculated as maximum intensity value of the affected spinal nerve/maximum intensity value of the asymptomatic side from region of interest (ROI) made on MRM was evaluated.
RESULTS
Twenty symptomatic foraminal stenosis cases (67%) showed the affected spinal nerve edema on MRM. The prevalence and VAS of leg pain at rest were significantly higher in the presence of spinal nerve edema group (95% and 67.0±36.4, respectively). The correlation coefficient between the VAS for leg pain at rest (53.0±33.6) and the spinal nerve edema ratio (1.3±0.3) was 0.647 (p<0.01).
DISCUSSION
Our study revealed the substantial correlation found between the spinal nerve edema ratio on MRM and the VAS for leg pain at rest in symptomatic foraminal stenosis. The correlation between spinal nerve edema and leg pain at rest has potential to clarify the pathology of symptomatic foraminal stenosis.
LEVEL OF EVIDENCE
IV.
Topics: Humans; Constriction, Pathologic; Spinal Stenosis; Prospective Studies; Leg; Lumbar Vertebrae; Spinal Nerves; Pain; Magnetic Resonance Imaging; Edema
PubMed: 34666199
DOI: 10.1016/j.otsr.2021.103119 -
The Journal of Hand Surgery, European... Jun 2024Distal nerve transfer is a refined surgical technique involving the redirection of healthy sacrificable nerves from one part of the body to reinstate function in another... (Review)
Review
Distal nerve transfer is a refined surgical technique involving the redirection of healthy sacrificable nerves from one part of the body to reinstate function in another area afflicted by paralysis or injury. This approach is particularly valuable when the original nerves are extensively damaged and standard repair methods, such as direct suturing or grafting, may be insufficient. As the nerve coaptation is close to the recipient muscles or skin, distal nerve transfers reduce the time to reinnervation. The harvesting of nerves for transfer should usually result in minimal or no donor morbidity, as any anticipated loss of function is compensated for by adjacent muscles or overlapping cutaneous territory. Recent years have witnessed notable progress in nerve transfer procedures, markedly enhancing the outcomes of upper limb reconstruction for conditions encompassing peripheral nerve, brachial plexus and spinal cord injuries.
Topics: Humans; Nerve Transfer; Peripheral Nerve Injuries; Brachial Plexus; Upper Extremity
PubMed: 38296247
DOI: 10.1177/17531934231226169 -
Anatomical Record (Hoboken, N.J. : 2007) Apr 2021A peridural membranous layer exists between the bony wall of the spinal canal and the dura mater, but reports on the anatomy of this structure have been inconsistent....
A peridural membranous layer exists between the bony wall of the spinal canal and the dura mater, but reports on the anatomy of this structure have been inconsistent. The objective of this study is to give a precise description of the peridural membrane (PDM) and to define it unambiguously as a distinct and unique anatomical entity. Thirty-four cadaveric sections of human thoraco-lumbar spines were dissected. On gross examination, the PDM appears as a smooth hollow tube that covers the bony wall of the spinal canal. An evagination of this tube into the neural foramen contains the exiting spinal nerve. The entire epidural venous plexus, including its extension into the neural foramina, is contained in the body of the PDM. Histological examination of the PDM shows a variable distribution of veins arteries, lymphatics, and nerves embedded in a continuous sheath of fibrous, areolar, and adipose tissue. The posterior longitudinal ligament may be considered a dense condensation of fibrous tissue within the membrane. Thus, the PDM is a unique, continuous, and complete anatomical structure. In the spinal canal, the PDM is adjacent to the periosteum. In the neural foramen, suprapedicular PDM and pedicular periosteum separate anatomically to form a suprapedicular compartment, bounded anteriorly by the intervertebral disc and posteriorly by the facet joint. Trauma or degeneration of the disc or facet joint may lead to inflammation and pain sensitization of PDM. This protective mechanism may be of considerable importance for the functioning of the spine under conditions of strain.
Topics: Cadaver; Dura Mater; Epidural Space; Humans; Spinal Nerves; Spine
PubMed: 32562360
DOI: 10.1002/ar.24476